branchmap: simplify update code
We drop iterrevs which are not needed anymore. The know head are never a
descendant of the updated set. It was possible with the old strip code. This
simplification make the code easier to read an update.
from mercurial.hg import parseurl
def testparse(url, branch=[]):
print '%s, branches: %r' % parseurl(url, branch)
testparse('http://example.com/no/anchor')
testparse('http://example.com/an/anchor#foo')
testparse('http://example.com/no/anchor/branches', branch=['foo'])
testparse('http://example.com/an/anchor/branches#bar', branch=['foo'])
testparse('http://example.com/an/anchor/branches-None#foo', branch=None)
testparse('http://example.com/')
testparse('http://example.com')
testparse('http://example.com#foo')